Housing systems for axial turbomachines such as, for example, airplane turbines comprise a housing in which vanes are customarily arranged in a crown shape. These vanes, that form a so-called “vane cluster”, should be sealed as pressure-tight as possible against the housing in order to avoid unnecessary flow losses during the operation of the associated axial turbomachine. However, large thermal gradients with correspondingly high loads in the area of the rear closing wall occur in the case of vane clusters with a large circumferential extension and a high closing wall. Therefore, after a certain size of the housing and/or of the vanes a continuous closing wall is no longer possible, so that the vanes are fastened by individual fastening elements on the housing. Such a housing system can be gathered, for example, from U.S. Pat. No. 4,194,869.
However, comparatively many slots are produced between the fastening elements and the housing by this type of fasting, which slots must be sealed by a sealing element in order to reduce the leakage flows occurring during operation. For example, sealing platelets (so-called “leaf seals”) or sealing rings that surround the outer vane feet are known from the prior art.
However, these known sealing elements are considered to have the disadvantageous circumstance that they are relatively expensive and complicated to mount and that their sealing action frequently weakens during the operation of the axial turbomachine. This leads to a reduced effectiveness and to a correspondingly elevated fuel requirement.